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windowscominteropcom-interop

When and why use CoLoadLibrary?

The description of CoLoadLibrary() says it does pretty much the same as LoadLibraryEx() - loads a DLL into the process. COM classes creation functions - CoCreateInstance() and CoGetClassObject() - both do load the necessary DLL into the process too.

Then why is CoLoadLibrary() needed in the first place and how should it be used?

Solution

  • Have a look at the code:

    mov     edi,edi
push    ebp
mov     ebp,esp
push    8
push    0
push    dword ptr [ebp+8]
call    dword ptr [ole32!_imp__LoadLibraryExW (71eb1214)]
pop     ebp
ret     8

    So it just calls:

    LoadLibraryEx( FileName, NULL, LOAD_WITH_ALTERED_SEARCH_PATH ).

    Presumably, the routine merely exists for backwards compatibility -- it probably has its roots in Win16.